(Photo contributor: Michael Stone, MD)
*The authors acknowledge the special contributions of Dimitrios Papanagnou, MD, and Michael Secko, MD, to prior editions.
Ultrasonography (US) is increasingly being applied in EDs for evaluation and management of patients with traumatic injuries and nontraumatic conditions. US is particularly useful in trauma. The extended focused assessment with sonography for trauma (eFAST) examination is a brief, repeatable, nonionizing, diagnostic exam used to detect gross blood in the abdomen, pericardium, and thorax in patients with blunt or penetrating torso trauma. The exam is limited to detecting free fluid as evidence of hemorrhage within an anatomic compartment, rather than the injury itself, because US is insensitive for visualizing solid organ injuries. Hemoperitoneum in the pediatric trauma patient is most often a result of hepatic or splenic injury and will typically appear as an anechoic (black) fluid collection on US.
Historically the focused assessment with sonography for trauma (FAST) exam, later modified to EFAST for visualization of the lungs, was intended for use in adults to detect massive hemoperitoneum in hemodynamically unstable blunt trauma patients to identify those who may need immediate laparotomy. The FAST exam includes 3 views of the abdomen (right upper quadrant [RUQ], left upper quadrant [LUQ], and pelvis) and a view of the pericardium. Later, views of the lung bases for hemothorax and pleura for pneumothorax were included to compose the EFAST exam. Furthermore, the role of the EFAST has extended to other scenarios such as penetrating trauma or undifferentiated hypotension, where EFAST can help the clinician prioritize management based on site of blood loss (chest, pericardium, or abdomen).
A low-frequency (1–5 MHz) curvilinear abdominal or phased array probe is typically used for its deeper penetration. Perform the scan with the patient in the supine position. Direct the probe indicator toward the patient’s head or the patient’s right side. When imaging the RUQ and LUQ, you may rotate the probe slightly to image in the plane of the intercostal spaces.
Obtain the following 4 views:
Hepatorenal space (Morison pouch) in the RUQ
Rectovesicular pouch (males)
Pouch of Douglas (females)
LUQ—subphrenic and splenorenal space
eFAST Views with Probe Position and Probe Types. (A) The 5 main US windows of the eFAST exam: (1) The right upper quadrant view of the hepatorenal recess; (2) the left upper quadrant view of the splenorenal recess; (3) the subxiphoid cardiac view; (4) the suprapubic view; and (5) transthoracic lung windows. (B) Probes used for US. A few probes that one may use in their clinical practice are shown. ...